Matches a backspace \u0008 if in a []; otherwise matches a word boundary (between \w and \W characters).

\t

Matches a tab \u0009.

\r

Matches a carriage return \u000D.

\v

Matches a vertical tab \u000B.

\f

Matches a form feed \u000C.

\n

Matches a new line \u000A.

\e

Matches an escape \u001B.

\040

Matches an ASCII character as octal (up to three digits); numbers with no leading zero are backreferences if they have only one digit or if they correspond to a capturing group number. (For more information, see Backreferences.) For example, the character \040 represents a space.

\x20

Matches an ASCII character using hexadecimal representation (exactly two digits).

\cC

Matches an ASCII control character; for example \cC is control-C.

\u0020

Matches a Unicode character using a hexadecimal representation (exactly four digits).

\*

When followed by a character that is not recognized as an escaped character, matches that character. For example, \* is the same as \x2A.

Matches any character except \n. If modified by the Singleline option, a period character matches any character. For more information, see Regular Expression Options.

[aeiou]

Matches any single character included in the specified set of characters.

[^aeiou]

Matches any single character not in the specified set of characters.

[0-9a-fA-F]

Use of a hyphen (–) allows specification of contiguous character ranges.

\p{name}

Matches any character in the named character class specified by {name}. Supported names are Unicode groups and block ranges. For example, Ll, Nd, Z, IsGreek, IsBoxDrawing.

\P{name}

Matches text not included in groups and block ranges specified in {name}.

\w

Matches any word character. Equivalent to the Unicode character categories
[\p{Ll}\p{Lu}\p{Lt}\p{Lo}\p{Nd}\p{Pc}]. If ECMAScript-compliant behavior is specified with the ECMAScript option, \w is equivalent to [a-zA-Z_0-9].

\W

Matches any nonword character. Equivalent to the Unicode categories [^\p{Ll}\p{Lu}\p{Lt}\p{Lo}\p{Nd}\p{Pc}]. If ECMAScript-compliant behavior is specified with the ECMAScript option, \W is equivalent to [^a-zA-Z_0-9].

\s

Matches any white-space character. Equivalent to the Unicode character categories [\f\n\r\t\v\x85\p{Z}]. If ECMAScript-compliant behavior is specified with the ECMAScript option, \s is equivalent to [ \f\n\r\t\v].

\S

Matches any non-white-space character. Equivalent to the Unicode character categories [^\f\n\r\t\v\x85\p{Z}]. If ECMAScript-compliant behavior is specified with the ECMAScript option, \S is equivalent to [^ \f\n\r\t\v].

\d

Matches any decimal digit. Equivalent to \p{Nd} for Unicode and [0-9] for non-Unicode, ECMAScript behavior.

\D

Matches any nondigit. Equivalent to \P{Nd} for Unicode and [^0-9] for non-Unicode, ECMAScript behavior.